Air Handling System

ABSTRACT

A system and method are provided which capitalize on heating and air conditioning ductwork to draw fresh air through a house and cool the attic. Outside air enters through open windows and is drawn into return air vents. A blower fan, which is housed within the duct assembly or an air handling unit, draws air through the return duct work and exhausts into an exhaust duct. A damper in the exhaust duct has an exhaust position and a return position. In the exhaust position, air exhausts through a vent in an attic space, where the attic space is vented to the outside. In the return position air continues to the heating and air conditioning unit. The present invention provides a means to direct the fresh air flow through a house using return vents while cooling the attic space without the use of an attic fan.

BACKGROUND OF THE INVENTION

The present invention relates generally to drawing fresh air through aresidential unit. More particularly, this invention provides a method ofdrawing in fresh air and exhausting the air through an attic.

Conventional air handling in occupied commercial structures must supplya minimum air change over, fresh air and oxygen. In residential units,where little air drafts in or out through structure cracks, windowseals, and the like, intentional means of fresh air intake and exhaustmay be desirable. In today's energy conservation climate, energyefficiency for any heating and air conditioning system is an objective,in addition to the air quality considerations. In tight commercialbuildings, and more and more in residential buildings, little air leakis present.

Conventional residential heating and air conditioning systems may havemultiple return sources, vents. For example, in a two story home theremay be a return on each level. These returns draw air into the ductsystem, which is then either heated or conditioned and distributed tovarious exhaust vents, which are often times in the floor or near floorlevel. In conventional systems, the same duct work is used for heatingand air conditioning, or air circulation if just the heating and airconditioning fan is used. The same duct work may supply exhaust for twofloors, exhausting near the ceiling of the first floor and near thefloor of the second floor, alternatively, exhausts may, for example,consistently be located near floor level with return vents located nearthe ceiling level.

There are a multitude of heating, cooling, and mechanical systemsavailable for residential units, each with their own benefits andcompromises. One conventional method for cooling a home is theinstallation of an attic fan. As an attic heats up in the summer, thisheat will also heat the interior of the house from the ceiling down.Installation of an attic fan 110, as shown for example in FIG. 1, willdraw in cooler outside air through vents 120 and drive circulated hotterair through the attic fan exhaust 110 to the outside. Preventingexcessive heating or cooling of the attic space can lower the insidetemperature of the house. An attic fan may be used to augment a primaryconventional cooling system. Attic heat can account for a substantialamount of the cooling load, perhaps 20 percent. An attic fan can beinstalled with a thermostat to turn on and off in accordance withtemperature settings and can in turn, lower the cooling load on an airconditioning system.

SUMMARY OF THE INVENTION

The present invention provides a system and method for drawing fresh airthrough a house and exhausting the fresh air into an attic space.

One aspect of the present invention is that fresh air is drawn inthrough opened windows or doors and into return vents of a heating andair conditioning system.

Another aspect of the present invention is that conventional airhandling units can be incorporated into an exemplary embodiments of thepresent invention.

Another aspect of the present invention is that existing duct work canbe modified to implement the present invention.

Another aspect of the present invention is that it can cool the atticand the house without air conditioning.

Another aspect of the present invention is the reduction of airconditioning load.

Another aspect of the present invention is that air is circulatedthroughout the house, and can be drawn into rooms, which lack fans orwindows.

Another aspect of the present invention is that it may be automaticallycontrolled with a thermostat.

Another aspect of the present invention is that it may be automaticallycontrolled with a an ambient temperature sensor.

Another aspect of the present invention is that it may be automaticallycontrolled via a combination of a thermostat and an ambient temperaturesensor.

Those skilled in the art will further appreciate the above-notedfeatures and advantages of the invention together with other importantaspects thereof upon reading the detailed description that follows inconjunction with the drawings.

BRIEF DESCRIPTION OF THE FIGURES

For more complete understanding of the features and advantages of thepresent invention, reference is now made to the detailed description ofthe invention along with the accompanying figures, wherein:

FIG. 1 shows a conventional attic fan;

FIG. 2 shows implementation of an exemplary embodiment of the presentinvention;

FIG. 3 shows an exemplary air handling unit and damper in accordancewith the present invention; and

FIG. 4 shows an exemplary steps for implementing the present inventionin accordance with an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention, as defined by the claims, may be better understood byreference to the following detailed description. The description ismeant to be read with reference to the figures contained herein. Thisdetailed description relates to examples of the claimed subject matterfor illustrative purposes, and is in no way meant to limit the scope ofthe invention. The specific aspects and embodiments discussed herein aremerely illustrative of ways to make and use the invention, and do notlimit the scope of the invention.

The present invention can be used to draw fresh air in and circulate itthrough the house. Air will draft from open windows or doors to openreturn vents in the duct system. A blower fan will draw the air throughthe return ducts. An ambient temperature sensor can be used to triggerinitiation of the fresh air system. Likewise a thermostat can be used totrigger the fresh air system. In accordance with one embodiment, thefresh air system can be activated depending on outside temperature, andin another embodiment the fresh air system can be activated depending ona thermostat. For example, it may be desired to invoke the fresh airsystem in accordance with the indoor temperature, irrespective of theoutdoor temperature. In yet another embodiment, a combination of ambientand indoor temperatures may trigger the fresh air system. For example,perhaps the fresh air system will be invoked when the ambienttemperature is at least five degrees cooler than indoor temperature.

The present invention can be used to cool the attic or at least reducethe heating of the attic during the day. The present invention willexhaust fresh air into the attic. This airflow in the attic will reducethe temperature in the attic or help maintain the temperature in theattic. The colder the outside air drawn into the house and into thereturn vents, the colder the exhaust air into the attic, and the moreeffective the attic cooling. As the attic space heats up during the day,the house heats up, too, from the top most ceiling down. The presentinvention can be used to reduce the attic temperature and in turn reducethe load on the primary air conditioning unit.

In the conventional attic fan shown in FIG. 1, outside air is not drawnthrough the house. Alternatively, an attic fan can be mounted in theceiling, exhausting into the attic space and venting air, for example,out of vents 120. In such a system, the air is only drawn into the atticfan, which is mounted in the ceiling. FIG. 2 shows an exemplary freshair system 200 in accordance with an exemplary embodiment of the presentinvention.

In an exemplary embodiment of the present invention, shown for examplein FIG. 2, outside air is drawn into multiple return vents 240, 241. Anynumber of return vents can be utilized with the present invention.Existing return vents can be closed off if desired when the fresh airsystem is activated. Varying the open return vents and the open windowsallows the user to better control the flow of fresh air through thehouse. Perhaps cold fresh air is not desired to flow from downstairswindows to the ceiling in the second floor, where a nursery is present,for example. Closing return vent 241, can minimize the draft fromdownstairs windows, window 275, for example to the second floor.Similarly, opening first floor interior doors and return vent 240 willdraw air from open window 275 through downstairs rooms 274, 276 and upinto the return duct work 215 via vent 240. To create the draw throughthe return duct work, in accordance with the present invention a fan(not shown) is employed in the air handling unit 210, where an exemplaryair handling unit is shown in greater detail in FIG. 3. Air exhaustedfrom the air handling unit fan is exhausted out a vent 230 into theattic space 250. Return duct work 215 provides the conduit from returnvent 240 to the air handling unit 210. Air is vented from the atticspace 250 to the outside via one or more vents 290.

In another embodiment, return vent 241 is open and window 285 is opencreating a direct draft in room 284. The return duct work for vent 241to the air handling unit is not shown but can either tie into duct work215 or may have a separate air handling unit, such as an air handlingunit dedicated to the second floor. This separate air handling unitcould tie into a separate heating and air conditioning unit or into anthe same heating and air conditioning unit. Tie in to the heating andair conditioning return is discussed below.

FIG. 3 shows an exemplary embodiment of the air handling system inaccordance with the present invention. Return air 315 enters the returnair duct 305, which may be a plenum with multiple ducts feeding into it.An air handling unit 310 fan 370 draws the return air 315 and exhaustsair to the damper duct 332. In the exhaust position 380, damper 382seals off the duct work returning to the heating and air conditioningunit, and air exhausts through vent 330 (230 in FIG. 2) into the atticspace.

While ducts 332 and 305 are shown with a rectangular cross section,alternate cross sections are possible in keeping with the spirit of thepresent invention. Likewise, vents, exhaust or return, can be of varyingshapes, circular, for example.

Fan 370 can be an inline fan, an axial, or a radial fan having an intake305 and an exhaust 332. The fan 370 can be direct drive or belt drivenby a motor 372. When the fan 370 is off, return air can still flowaround the fan or a second damper can direct air around the fan toconnect to exhaust duct 332. When full return air is desired, forexample when damper 382 is in the return air position 384, a heating andair conditioning fan further downstream may draw the return air to aheating and air conditioning unit return. Fan 370 may augment thedownstream return fan. In yet another embodiment, the return to theheating and air conditioning unit is close to the exhaust duct 332 andfan 370 functions as a return fan for the heating and air conditioningunit. Additionally, the damper 382 may be at some point in between theexhaust position 380 and the return position 384. In such an embodiment,air may be vented to a second attic space down stream from the damper382.

The damper 382 can be rotated by an electric motor 320. Rotating of thedamper can be tied 354 to a control unit 355 which also controls the fanmotor 372, for example, via line 356. A thermostat 350 can feed into acontrol unit 355. Either or both of the thermostat and the control unitmay be located in the attic space or in a convenient hallway, forexample. Two or more thermostats may be used to control activation ofthe fresh air system, one in the attic space and one or more within thehouse. In addition or alternatively, an ambient temperature sensor 357may be used to exclusively control the fresh air system or may be usedin combination with thermostats.

FIG. 4 provides exemplary steps in implementing the fresh air system, inaccordance with a method of the present invention. A reading is takenfrom an ambient temperature sensor 410 and compared to the thermostattemperature. When the ambient temperature is less than the thermostattemperature 430, then the damper is rotated to the exhaust position 440.Open windows and doors as desired 450. Activate the blower fan 460 andclose some return vents, but not all return vents, as desired to directfresh air flow 470.

While specific alternatives to steps of the invention have beendescribed herein, additional alternatives not specifically disclosed butknown in the art are intended to fall within the scope of the invention.Thus, it is understood that other applications of the present inventionwill be apparent to those skilled in the art upon reading the describedembodiment and after consideration of the appended claims and drawing.

1. An air handling apparatus, the apparatus comprising: at least onereturn air source; duct work connecting the at least one return airsource to an electric fan; an exhaust air duct for air exhausted out ofthe fan; and a damper to redirect air from traversing the exhaust airduct to an attic vent.
 2. The air handling apparatus according to claim1, further comprising: a motor which positions the damper.
 3. The airhandling apparatus according to claim 2, further comprising: athermostat which controls the motor for positioning the damper.
 4. Theair handling apparatus according to claim 3, wherein: the thermostatalso controls the electric fan.
 5. The air handling apparatus accordingto claim 2, further comprising: an ambient temperature sensor whichcontrols the motor for positioning the damper.
 6. The air handlingapparatus according to claim 5, wherein: the ambient temperature sensoralso controls the fan.
 7. The air handling apparatus according to claim2, further comprising: a control unit, wherein said control unitreceives inputs from a thermostat and an ambient temperature sensor; andwherein the control unit controls at least one of the fan and the motorwhich positions the damper.
 8. The air handling apparatus according toclaim 1, wherein: the fan is any of an axial propeller fan or a radialsquirrel cage fan.
 9. The air handling apparatus according to claim 1,further comprising: a screen at the attic vent to prevent particulatefrom accumulating in the duct when air is not exhausted out of the atticvent.
 10. The air handling apparatus according to claim 1, wherein: theexhaust air duct runs through at least a portion of attic space, andwherein the attic vent is positioned on any side of the exhaust airduct.
 11. The air handling apparatus according to claim 1, furthercomprising: a first seal for each of first damper positions and a secondseal for a second damper position.
 12. The air handling apparatusaccording to claim 2, further comprising: a wall console for turning onthe fan.
 13. The air handling apparatus according to claim 4, wherein:damper position is selected via the wall console.
 14. A method of movingair through an attic, the method comprising: directing air exhaustedfrom a fan to an air duct which runs at least partially into an attic;positioning a damper to direct air from the air duct to a vent within aninterior attic space, wherein air exhausts out of the vent into theattic; and providing exterior vents which allow exhausted air to ventout from the interior attic space to the outside.
 15. The methodaccording to claim 14, wherein: the fan is an inline fan or a boosterfan.
 16. The method according to claim 14, further comprising opening atleast one window or at least one door, wherein outside air is drawn toan at least one return air vent; directing return air via at least oneduct to the fan.
 17. A method of directing fresh air through a house,the method comprising: opening a window in a first floor; closing areturn air vent in a second floor; opening a return vent in a firstfloor; rotating a damper within an exhaust duct to an exhaust position;activating a blower fan just upstream of the damper and drawing freshair from the opened first floor window through the open return vent tothe blower fan; and exhausting air from the fan to the exhaust duct andout a vent into an attic space, wherein the attic is vented to theoutside.
 18. A system to selectively direct fresh air flow through ahouse and to cool an attic, the system comprising: at least twocloseable return air vents; a return duct work which connects to the atleast to closeable return air vents; an air handling unit which connectsto the return duct work, wherein the air handling unit comprises a fan;an exhaust duct which connects to the air handling unit, wherein theexhaust duct comprises a vent directed towards an attic space and housesa damper; and at least one vent from the attic space to an outsidespace, wherein the damper is rotate-able between an exhaust position anda return position and when the damper is in the exhaust position freshair exhausts through the vent into the attic space.